The operating system manages shared resources
Applications depend on operating-system services instead of controlling every hardware component directly.
Principal responsibilities
Process management
Schedules running programs and shares CPU time.
Memory management
Allocates RAM and protects one process from another.
File management
Organises files, folders and access permissions.
Device management
Uses drivers to communicate with hardware.
User interface
Provides graphical or command-based interaction.
Security and networking
Controls accounts, access and network services.